Plant Preview

Welcome to Plant Preview, a blog dedicated to helping gardeners learn about gardening techniques and preview new plant cultivars. Read about new plants here first and hear how your "comrades in compost" are making use of new plant introductions in their gardens and landscapes. Blog author Geri Laufer is a life-long dirt gardener, degreed horticulturist, author and former County Extension Agent. Plant Preview is copyrighted by Geri Laufer.

Friday, November 9, 2012

Wood Chips Connoisseur

gardengeri on top of a load of free wood chips
Free wood chips (along with free bags of pine straw collected from curbs across nearby neighborhoods) are the mainstay of my garden. In Atlanta's warm climate, wood chips biodegrade to yield rich black organic humus similar to woodland soil in one year.I continually replenish organic matter in the form of mulch on the surface, or as compost dug into the soil, increasing the organic content and improving the soil structure of my Georgia red clay. 

In order to obtain desirable wood chips I ask the driver a couple of questions. 

Q. How sharp is your chipper/shredder? 

A. If he says "I put new blades on on Monday" we are good to go. I prefer a sharp chipper which produces small, neat wood chips. In contrast, a dull chipper produces long strips of wood that are unsightly as mulch and are slower to break down as compost. 

Wood chip mulch
Q. Where do these wood chips come from? 

A. Ideally, if the crew has been trimming back healthy tree limbs to clear right of way along power lines, I can be pretty sure of healthy, safe, disease-free chips. 

Wood & Leaf Chips
Q. Time of year and Summer chips v.s. Winter chips

A. This brings in the Nitrogen:Carbon Ratio. Summer wood chips contain large amounts of green leaves that add an important component of Nitrogen to the compost or mulch. Bare, leafless limbs in winter are composed of wood rather than leaf tissue, and add a higher component of Carbon. Evergreens can add high-N leaves even in winter, as is the case with wood chips from Christmas trees. 

When a new load of wood chips is delivered, the pile heats up during the immediate process of bacterial decomposition. If I insert a garden fork to open up the pile, steam rises from the disturbed chips. After the pile cools down, the development of white fungus strands (mycelium) on the wood chips signifies that the "friendly fungi" present are actively at work and the chips are well on their way to breaking down to compost and humic acid.

rich woods soil 
Basically,  the wood chips add bulk to the soil structure three ways:
1. fibrous organic matter of the chips themselves
2. biological mass of filamentous fungi that grows on them
3. transitory waves of beneficial bacteria populations 
This creates a favorable environment for worms and microorganisms.   

Digging Deeper: For Further Reading:

OK State Recycling Yard Waste: Don’t Bag It  (although if everyone read this, I would get no more free pinestraw)

1 comment: